Activity 1
f(x) = 3x − 2 → f(5) = ?
Show step-by-step solution
f(5) = 15 − 2 = 13.
EDUCADORS / Learning guide
Secondary school · Functions
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Original educational content
Learn the concept
Learning objective: Relate input values to a function’s output.
In f(x) = mx + b, m is the gradient and b is the intercept.
Worked example
f(x) = 2x + 3 → f(4) = 11
Practise and check
Activity 2
f(x) = −x + 6 → f(2) = ?
Show step-by-step solution
f(2) = −2 + 6 = 4.
Activity 3
g(x) = x² − 1 → g(3) = ?
Show step-by-step solution
g(3) = 9 − 1 = 8.
Learning tip: In f(x) = mx + b, m is the gradient and b is the intercept.
Practice · Interactive labs
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Learning guide
Choose a course suitable for your level and learn at your own pace. Explore key ideas, practise with examples and check your results.
- Choose your level
- Step-by-step learning
- Suggested resources